Amblyopia, also known as a lazy eye, is a decrease in visual capacity that occurs mainly due to the lack of stimulation of the affected eye during the development of vision, being more frequent in children and young adults.
It is detected by the ophthalmologist, and determining the cause is essential to decide what type of treatment is indicated, such as wearing glasses or an eye patch, and whether or not there will be a cure. In addition, to cure amblyopia, it is important that this visual change is identified and treated early, as persistence for many years can cause irreversible atrophy of the eye nerves and prevent vision correction.
Amblyopia can appear from mild to severe, affect only one or both eyes, and can have several causes, from functional causes, when the vision of an eye is discouraged by visual difficulties, to organic causes, in which an injury makes it difficult to eyesight. So, generally, the brain tends to favor the vision of the eye that sees better, and the vision of the other eye is increasingly suppressed.
The main types are:
1. Ambliopia estrábica
It is the most common cause of amblyopia, which occurs in children who are born with strabismus, popularly known as “bladder”. In these cases, the child’s brain is able to adapt the vision so that it is not duplicated, and ends up suppressing the vision of the deviated eye, ignoring the vision captured by this eye.
Although it is able to adapt the child’s vision to strabismus, this suppression of stimuli results in reduced vision of the affected eye. This can be curable with treatment, however, it is important that it is done as early as possible, even in the first years of life, to allow vision to be recovered completely.
- Treatment : until 6 months of age, strabismus is usually treated with an eye patch, or eye plug, which occludes the eye without alteration and stimulates the squint to remain centralized and able to see. However, if the change continues after this age, the ophthalmologist may recommend surgery to correct the action of the eye muscles, making them move in a synchronized manner.
Check out more details on how to treat strabismus in babies and treatment options for adults .
2. Amblyopia refracional
This type of alteration occurs when there are refractive problems in the vision, such as myopia, hyperopia or astigmatism, for example. It can be of the types:
- Anisometropic : when there is a difference of degrees between the eyes, even if it is not very intense, causing the vision of an eye to predominate over the eye with the worst vision;
- Ametropic : happens when there is a refractive problem of high degree, even if bilateral, and usually happens in cases of hyperopia;
- Meridional : it is caused by astigmatism not properly corrected, which can also cause suppression of vision.
Refractive errors are important causes of amblyopia, and must be detected and treated as soon as possible to prevent them from causing an irreversible visual change.
- Treatment : it is necessary to correct refractive errors by wearing glasses to the degree recommended by the ophthalmologist.
Learn how to identify signs that your child needs to wear glasses to avoid amblyopia.
3. Amblyopia due to deprivation
Amblyopia due to deprivation of stimuli, or ex-anopsia, occurs when diseases arise that prevent light from entering the eye for correct vision, such as a congenital cataract, opacities or corneal scars, for example, which interrupts visual development.
In some cases, even the use of the eye patch to treat strabismus, which is used constantly, can be a cause of amblyopia in the eye that is deprived of vision.
- Treatment : it is oriented according to the cause, in order to try to correct the initial visual alteration, such as surgery to remove the cataract. The earlier the treatment is performed, the greater the chances of vision recovery.
Symptoms of amblyopia
Generally, amblyopia does not cause symptoms, appearing and worsening silently, mainly because it is a problem that usually affects children.
Therefore, it is important to be aware of signs of misalignment of the eyes, which indicate strabismus, or visual difficulties, such as difficulties in learning at school, closing the eyes or moving objects away to read, for example, which indicate refractive problems. If they arise, you should schedule an appointment with the ophthalmologist, who will perform the eye examination. Better understand how the eye exam is done and when it is necessary to do it